Towards the Web of Quantum Chaos Diagnostics

Understand

We study the connections between three quantities that can be used as diagnostics for quantum chaos, i.e., the out-of-time-order correlator (OTOC), Loschmidt echo (LE), and complexity.

• We generalize the connection between OTOC and LE for infinite dimensions and extend it for higher-order OTOCs and multi-fold LEs.
• Novel applications of this intrinsic relation are proposed.
• We also propose a relationship between a specific circuit complexity and LE by using the inverted oscillator model.